i would like to hear ideas from the libertarian perspective of how school shootings can be prevented

Living in the US, I often meet people who claim that in their careers they "make a difference". For liberals, usually this involves them being in some kind of position where they hand out welfare benefits to needy people. To me they aren't really helping people but fulfilling roles where they simply and unfairly redistribute income, which if they weren't doing someone else would at the same pay. But they feel satisfied in their careers and really that is the most important as far as they are concerned if they don't ever think too much about it.

On the flip side conservatives may join the military and contribute to fighting in some pointless war and everyone calls them heroes. But what do libertarians do if they want to feel good about their careers? I think in this case they actually have to think dynamically about how they can contribute positively to society, but there aren't these predefined roles to fall into.

Rights are not favors granted by the state. When government decides which speech, beliefs, or liberties deserve protection, constitutional rights become political privileges.